Question: Which of the following ordered pairs represents a solution to the equation below? $(-2, 7) (-1, 6) (0, 0) (1, -2) (2, -4)$ $y = -3x+2$
Solution: We can try plugging in the x-value of each ordered pair into the equation. If we evaluate and get the y-value of the ordered pair, then that ordered pair is a solution! Let's consider $(-2, 7)$ If we plug in $-2$ for $x$ and evaluate, do we get $7$ $y = (-3)(-2) + 2 = 6 + 2 = 8$ Let's consider $(-1, 6)$ If we plug in $-1$ for $x$ and evaluate, do we get $6$ $y = (-3)(-1) + 2 = 3 + 2 = 5$ Let's consider $(0, 0)$ If we plug in $0$ for $x$ and evaluate, do we get $0$ $y = (-3)(0) + 2 = 0 + 2 = 2$ Let's consider $(1, -2)$ If we plug in $1$ for $x$ and evaluate, do we get $-2$ $y = (-3)(1) + 2 = -3 + 2 = -1$ Let's consider $(2, -4)$ If we plug in $2$ for $x$ and evaluate, do we get $-4$ $y = (-3)(2) + 2 = -6 + 2 = -4$ Thus the only ordered pair that is a solution to the equation is $(2, -4)$ We come to the same answer by plotting the points and the equation. $2$ $4$ $6$ $8$ $\llap{-}4$ $\llap{-}6$ $\llap{-}8$ $2$ $4$ $6$ $8$ $\llap{-}4$ $\llap{-}6$ $\llap{-}8$